GB453517A - A method and apparatus for the treatment of alkali-metal amalgam obtained in electrolytic cells having mercury cathodes - Google Patents

Abstract

<PICT:0453517/III/1> Alkali metal amalgam produced in an electrolytic cell is passed through a succession of vessels containing alkali lye at a temperature of 40--120 DEG C. in which the amalgam is decomposed with formation of caustic alkali, the reaction being assisted by the action of contact electrodes of graphite resting on the amalgam. Heating may be effected by a hot water or steam jacket, by electricity or by burning of the hydrogen produced in the decomposition. The drawing shows the first of a succession of heat-insulated metal chambers through which the amalgam flows for decomposition by means of contact electrodes d. Amalgam flows to the next chamber through a seal l in which is immersed a partition k provided with a bent pipe m whereby the lye traverses the chambers in the reverse direction to the amalgam. A heating jacket b is provided at the bottom or at the bottom and sides. Concentrated lye is drawn off at o and hydrogen at g. Less concentrated lye may be drawn off from the other cells if desired. The last decomposition chamber of the series may be cooled instead of heated in order that the mercury may re-enter the electrolytic cell in a cool condition. Alternatively, the cathode contact head of the electrolytic cell may be cooled.